Arun - is watershed a function or a script? In this case, I suspect that it is a script and does ot have a function signature. What does this code at C:\Users\kk\Documents\MATLAB\watershed.m look like?
Or, perhaps you are trying to use the watershed function from the Image Processing Toolbox and your function at C:\Users\kk\Documents\MATLAB\watershed.m is shadowing the other. If this is true, then you may want to renmae your function/script or remove it altogether.
